Boeing recently unveiled the suit that astronauts will be wearing when they ride their upcoming Starliner capsule to the International Space Station (ISS). Officially called the Starliner Ascent and Entry Suit, it also answers to "Starliner spacesuit". Aside from its bold "Boeing blue" color, the Starliner spacesuit has numerous features worth noting. It is quite different in several ways from any suit that astronauts have ever worn before. These differences reflect an emphasis on mobility and comfort, efforts to blend the suit with its host spacecraft, and the specific emergency scenarios that the suit is designed for.

The Basics

The most important thing to understand about the Starliner spacesuit is its role an "ascent and entry" suit. As such, it is only designed to be worn during launch and landing of the spacecraft. You won't see astronauts spacewalking in this suit (at least not for long!). The primary function of an ascent and entry suit is to keep the occupant alive if there is a problem inside the crew compartment during launch or landing. The scenarios with the highest probability (though still relatively unlikely) are loss of cabin pressurization or an internal fire.

Before getting to the specifics of the Starliner spacesuit, let's discuss the attributes of ascent/entry suits in generic terms. Previous generations of these suits have been derived from the pressure garments worn by pilots of high-altitude reconnaissance aircraft like the U-2 and SR-71. In some cases, the differences were negligible. Whether worn in an airplane or a spacecraft, the job such a suit is to provide its occupant with a tolerable atmospheric pressure, even when the outside pressure conditions are lethal.

Doing your job while fighting the resistance posed by a pressurized suit can be difficult. Astronauts are already battling the G effects of punching through the atmosphere, so there's no point in making things even harder on them. The accepted process is to button up all of the seals of the suit prior to launch or re-entry, but not pressurize. Astronauts instead rely on the cabin pressurization system to keep them safe. Sensors on the suit can detect if the cabin pressure drops below acceptable levels and instantly pressurize the garment as necessary.

A fire inside of the cabin is a serious situation. Even though many of the hazards that doomed the Apollo 1 crew have been mitigated, that tragedy is a stark reminder of how quickly a bad situation can become much, much worse. In the event of a cabin fire during launch or landing, the suit's job is to protect the astronaut from heat and flames while providing them with breathable air. Flame-resistant fabrics, such as Nomex, aid in the former task. Bottled nitrogen and oxygen address the latter.

Mobility and Comfort

As pressure suits go, Boeing's blue suit certainly looks comfortable. It appears much less restrictive than other ascent/entry suits. The shoes are particularly telling. I'm pretty sure I recently saw something similar at Foot Locker. In fact, Reebok had a hand in designing the Starliner spacesuit shoes.

An inflated pressure suit will rigidize to some degree. Astronauts most overcome this rigidity for every movement they make. The default pose of a pressurized suit is an upright, standing position…not so comfortable if you're still strapped into your seat. That's where the blue suit's horizontal torso zipper comes into play. Astronauts can zip up while seated and give the suit a more accommodating posture when pressurized.

The helmet on the Starliner spacesuit is a huge departure from traditional head gear. It has the standard polycarbonate visor, but the rest of the helmet is soft. The suit fabric provides a hinge in the rear of the helmet. A zipper along the front of the neckline secures the helmet in the 'down and locked' position necessary for pressurization. This configuration allows the helmet to be unzipped and tilted out of the way when not in use…making the Starliner spacesuit the world's most expensive hoodie.

Starliner Compatibility

While a soft helmet provides obvious comfort benefits, you have to wonder how much head protection it provides. Old-fashioned leather football helmets come to mind. Rest assured that Boeing did not overlook this fundamental helmeting chore. The head-protection elements of the suit are integrated into the communication cap found beneath the helmet's soft outer skin. This headgear also houses the astronaut's headset and microphones. Most obvious among the protective features is a contoured plastic panel covering the back of the astronaut's skull.

Former astronaut Chris Ferguson tried out the Boeing suit in a mockup of the Starliner crew compartment. (Boeing image)

The suit (and presumably the communication cap) are available in different sizes. But there is only one size of head protection plate. That's because this plate is shaped the match the headrest of the Starliner's seats. When you're pulling a few positive G's on your way to the ISS, a secure, comfortable headrest is a big plus. This is just one example of how the Starliner spacesuit has been tailored to integrate with the interior of the spaceship that it will be used in.

Many of the onboard control interfaces on the Starliner will use touch screens. These types of screens are not usually compatible with gloved hands. Boeing developed a material for the blue suit gloves that will work with touch screens. This material is on the exterior of the gloves at the thumb and first two fingers.

Emergency Scenarios – A Tale of Two Suits

There are tremendous differences between the Starliner spacesuit and the ascent/entry suit that was worn by astronauts in the space shuttle, the Advanced Crew Escape Suit (ACES). Actually, shuttle astronauts wore four different ascent/entry suits during the program's history. The evolution of those suits reflected a similar evolution in the perceived dangers of flying the shuttle.

The suit features a soft, lightweight helmet that uses a zipper to secure it into position. (Boeing image)

The first four shuttle missions were considered test flights. Ejection seats were installed on the orbiter Columbia. The two crew members on each mission wore the Shuttle Ejection Escape Suit, which was very similar to the suit worn by SR-71 pilots of the time.

Starting with mission STS-5, the ejection seats were removed and shuttle crews went to space in what amounted to standard military flight suits and a helmet. NASA was confident that astronauts could ride the shuttle up or down in a shirt-sleeve environment. That all changed following the 1986 loss of Challenger during launch. Thereafter, astronauts wore the familiar orange pressure suits that would help them survive in a few of the countless possible emergency scenarios. First was the Launch Entry Suit (LES). The improved ACES came along in 1994.

Because the space shuttle landed as a glider, any emergency that would prevent landing at one of the few coordinated runways left the crew with few options…none of them desirable. Experts felt that the astronauts' best chance for survival in such a situation was to evacuate the shuttle and conclude their mission hanging from the risers of personal parachutes.

Like other contingency scenarios that emerged from the shuttle program, the actual likelihood of successfully jumping from a crippled orbiter was often the subject of moot debate in NASA cafeterias and break rooms. But post-Challenger astronauts were equipped to give it a try if push came to shove.

The ACES launch/landing suit worn by space shuttle crews was a very different from the Starliner Spacesuit. Each was designed to handle emergency scenarios that are unique to their host vehicle. (NASA image)

In addition to the pressurization features that would sustain life in rarefied, high-altitude air, the LES and ACES were mated with parachutes. There was a strong chance that any bailout would be over water. The suits' orange color was meant to help rescuers locate the downed crewmen in open ocean. Each astronaut was also equipped with an inflatable life raft. Pockets all over the suit held various survival gear such as flares, seasickness pills, and pouches of drinking water. The ACES actually qualified as an immersion suit that could keep its inhabitant afloat and alive for many hours if they had the misfortune to land in frigid water.

One glance at the Starliner spacesuit tells you that it was designed for a very different kind of emergency. There's no parachute…no life raft...no dye marker. In fact there is very little room to stow any survival gear. And who wears a blue survival suit in the ocean? Someone who doesn't want to be rescued…that's who!

No, future Starliner astronauts do not have a death wish. The truth is that the features of Boeing's suit reflect how an actual Starliner emergency is likely to unfold. First of all, the Starliner is a capsule that returns to Earth via parachute. Unlike the space shuttle, there is no reasonably plausible scenario where the crew is better off abandoning their ship. In fact, the crew capsule is probably the safest place they can be. So there is little point in taking up extra volume and mass with personal parachutes.

All previous US-designed capsules have landed in the ocean. The Starliner is the first that is intended to come to rest on solid ground. Once again, the life raft, and other ocean-specific survival supplies that were found on the ACES simply are not needed on the blue suit. Of course, there is a possibility that a distressed Starliner may land in the ocean. The floating capsule would serve as the crew's lifeboat in that situation. The same is true if the crew comes down in a harsh climate on solid ground. The Starliner capsule itself provides much of the emergency survival gear that shuttle astronauts were forced to wear on the ACES.

Coming Soon

Boeing's new suit offers several new variations on traditional themes with pressure suits. Success with this suit will likely influence other designs currently on drawing boards. Operational use of the Starliner Ascent and Entry Suit could come quite soon. The first manned Starliner mission is currently scheduled for August of 2018. I'm sure that we'll all be watching and hoping that the blue suit's safety features are never necessary.

I'd like to thank Boeing for answering numerous 'outside the box' questions about their new suit. Thanks also to former ACES technician, Cody McNeil, for educating me on that system.

Terry is a freelance writer living in Lubbock, Texas. Visit his website atTerryDunn.organd follow him onTwitterandFacebook. You can also hear Terry talk about RC hobbies as one of the hosts of theRC Roundtablepodcast.